Pepperl+Fuchs ICDM-RX/MOD Manual page 6

ICDM-RX/MOD User Manual
Overview
Term
A form of Ethernet connectivity that provides a level of guaranteed delivery and data
Ethernet TCP/IP verification. This is used for many upper layer protocols such Modbus/TCP and can
be also used for transferring Modbus/RTU and Modbus/ASCII messages.
Local Slave Device A local slave device is one that is connected directly to a serial port on the gateway.
Master (or Client) The method of operation when a PLC, a gateway, or an application is operating as a
Mode Master or the message originator.
An ASCII, or character based, form of Modbus. The base message is the same as
Modbus/ASCII
Modbus/RTU, but the format is somewhat different.
The standard Modbus messages, in hexadecimal format, that are typically
transmitted over serial lines but can also be transmitted over other communication
Modbus/RTU
methods such as wireless or Ethernet TCP/IP socket connections.
Note: Modbus/RTU over Ethernet TCP/IP is not the same as Modbus/TCP.
An Ethernet based form of Modbus communication. The base message is the same
Modbus/TCP as Modbus/RTU, but a special Modbus header is included for packet identification
and routing purposes.
The process where a PLC or Application requests data on a continual basis. In this
Polling operation the Master sends the request messages while the Slave responds to the
messages.
A public slave device is one that can communicate to all master(s) on the Modbus
network.
Public Slave
Device
Note: If a device is not specifically specified as a "public" or "private" slave device,
A private slave device is one that can only communicate to a master that is connected
Private Slave
on the same serial bus, such as RS-485 or RS-422. Private slave device cannot
Device
communicate to other masters on the Modbus network.
Received Device
The original device ID received in the Modbus message from a Modbus master.
ID
Remote Slave A remote slave device is either a slave Modbus/TCP device or a serial slave device
Device attached to another gateway and accessed as a remote Modbus/TCP device.
Slave (or Server)
The method of operation when a PLC, a gateway, or an application is operating as a
Slave or the message receiver.
Mode
The method used to communicate between devices while communicating over
Sockets
Ethernet TCP/IP.
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then it can be assumed to be a public device.
Definition